Discovery and Progress of Solid-State Perovskite Solar Cells

ConspectusThe discovery and development of solid-state perovskite solar cells (PSCs) has reshaped the trajectory of photovoltaic research and commercialization. In 2012, our first report of a long-term stable solid-state PSC initiated a new field, which triggered a certified power conversion efficiencies (PCEs) of 27.3% surpassing the PCE of single-crystal silicon solar cell. Today, with the perovskite/Si tandem devices approaching 35%, PSCs have become leading candidates to meet the terawatt-scale demand projected for Net-Zero carbon targets by 2050. Our research has advanced PSCs from fragile liquid-junction devices to robust solid-state architectures through innovations in materials chemistry, crystal engineering, and device design. The adduct intermediate method emerged as an essential strategy to regulate perovskite crystallization, which is now widely used to make high-quality perovskite films. Compositional engineering further pushed the frontiers, particularly with FA/Cs-based systems that stabilized the photoactive α-phase and achieved >26% PCE. Better understanding the role of A-site organic cation is important to design perovskite compositions. Device stability─long a critical challenge─has been addressed through additive and interface engineering. We demonstrated facet-dependent stability, revealing that the (111) facet resists humid degradation, and developed facet-engineered films with enhanced durability. Interface treatments, including carbazole-based self-assembled monolayers and tailored passivation agents, mitigated non-radiative losses and ion migration. Spiro-MeOTAD, while central to early devices, was stabilized via degassing and photo-doping strategies, while dopant-free hole conducting materials opened alternative routes to thermal robustness. Scalability is equally vibrant for commercialization. We reported kilogram-scale aqueous synthesis of ultrapure FAPbI₃ precursors, reducing impurity-driven traps and enabling inverted devices with >25% PCE and long operational lifetimes. To translate this chemistry into manufacturing, we developed a D-bar coating process that rapidly deposits uniform large-area perovskite films in seconds, demonstrating high throughput with minimal waste. Alongside blade, slot-die, and vapor deposition, these approaches outline practical paths to multi-square-meter PSC modules. Looking forward, PSCs are ready to enter the market, with tandem perovskite/Si devices expected first, followed by high-efficiency single-junctions. Beyond photovoltaics, halide perovskites promise impact across optoelectronics, from light-emitting diodes to photodetectors and memristors. The extraordinary rise of PSCs exemplifies how careful materials design, guided by chemical principles and interfacial understanding, can rapidly transform an energy technology from concept to commercial reality.